Lifetime Attributable Breast Cancer Risk Related to Lung CT Scan in Women with Covid19

Purpose: Organ, effective dose, and Lifetime Attributable Risk (LAR) of breast cancer incidence related to lung Computed Tomography (CT) scans were evaluated. Seven hundred thirty-five female patients (20-50 years old) with Coronavirus (COVID-19) in four medical imaging centers in Tehran, Iran, were surveyed. Patients’ data, including age, sex, and exposure information (Kilovoltage (KVp), milliampere-second (mAs), pitch factor, Computed Tomography Dose Index (CTDIvol), and Dose Length Product (DLP)) were extracted from dose report pages in picture archiving and communication systems (PACS). Materials and Methods: Patients were divided into six age groups of 20-25, 25-30, 30-35, 35–40, 40-45, and 45–50 years. Breast, thyroid, lung, and heart absorbed doses, and also effective doses, were calculated by National Cancer Institute (NCICT) software, and LAR of breast cancer incidence has been evaluated by the Biological Effect of Ionizing Radiation (BEIR) VII in phase 2 report. Results: The average doses of breast, thyroid, lung, the heart were 3.97, 4.75, 4.10, and 3.37 mGy, respectively. Also, the average effective dose was 2.56 mSv. The average LAR of breast cancer in female patients was 7.45 per 100,000 exposures, decreasing dramatically with age. It was clear that exposure parameters and organ absorbed dose were significantly different between medical imaging centers (P value 0.05). Conclusion: Although the CT scan is a useful instrument in the diagnosis of Corona disease, it should be suggested with caution due to the increased risk of breast cancer, especially in younger women and pediatrics. Also, low-dose CT scan protocols are recommended to minimize radiation effective and absorbed doses.